Thermodynamic and Mechanistic Insights into Paracetamol Removal from Aqueous Solutions by Graphitic Carbon Nitride Nanosheets

This study explored the potential of raw graphitic carbon nitride (g-C₃N₄) as a low-cost adsorbent for removing paracetamol from water. The material's structure and properties were analyzed using various techniques, including X-ray diffraction (XRD), Fourier-transform infrared spectroscopy (FTIR), Ultraviolet visible (UV-Vis) spectroscopy, and Transmission electron microscopy (TEM). Factors affecting paracetamol adsorption, such as pH, contact time, adsorbent dosage, and initial paracetamol concentration, were investigated. The results showed that a maximum adsorption capacity of 1.1 mg/g was achieved at 25 oC within 60 minutes. Both Langmuir and pseudo-second-order models accurately described the adsorption behavior. Density functional theory (DFT) confirms the stability of the complex formed between Paracetamol and Graphitic carbon nitride (g-C₃N₄), and Molecular dynamics (MD) and FTIR confirm the stability of H-bond formation a high adsorption energy of – 38.640 x10-3 kcal/mol. These findings suggest that modified graphitic carbon nitride can be a promising, eco-friendly, and affordable adsorbent for removing pharmaceutical contaminants from water.